Date: Mon, 13 Sep 2004 09:56:16 -0500
Reply-To: Aerowolf <aerowolf@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Aerowolf <aerowolf@GMAIL.COM>
Subject: Re: Reverse Vanagon syndrome??
In-Reply-To: <69BC1320-050A-11D9-97E5-000A95A8745E@coreaddicts.com>
Content-Type: text/plain; charset=US-ASCII
Actually, leaky air would be a good cause of it.
See, the so-called 'gas pedal' doesn't control the amount of gas that
goes into the engine, it controls the amount of /air/ that goes into
the engine. (It's called a 'throttle' because that's what's used to
throttle the speed of the motor.)
The FCU (fuel control unit, aka the electronic control unit or
'computer') uses the information from the AFM to determine how much
fuel to inject. This only works, however, if the amount of air that's
going into the engine is being correctly reported by the AFM -- and if
more air is coming in than the AFM reports, the result will be too
little fuel and too much air -- a "lean" condition. (and since the
throttle is in the throttle body, AFTER the AFM in the intake system,
it relies on no leaks being there.)
If the injectors were clogged or dirty, it would affect everything
(and either give you no power anywhere, or give you dirty black smoke
since it would be injecting none of the time or all of the time, even
during the exhaust stroke).
What I'd suggest would be to try sealing it with duct tape to see if
it runs better, and if it does, get a new hose or a smaller clamp or
something. I don't recall my own hose connection being that cramped,
though... make sure there's nothing pushing your AFM/air filter into
an artificial position?
Cheers!
-Kyle
On Sun, 12 Sep 2004 16:23:46 -0600, Parker Beeson
<parker@coreaddicts.com> wrote:
> I seem to be experiencing the reverse of what I've read about Vanagon
> syndrome (tried searching the archives). Highway speeds and cruising
> for hours is fine, but off the mark acceleration and low speeds are
> *really* bogging down. If I ease into acceleration I'm okay, but if I
> push any significant gas off the line the van struggles a LOT and
> doesn't want to go. Accelerating from say 40-55mph on the highway is
> fine also. Doesn't sound rough at all at idle... just doesn't go off
> the line.
>
> The only thing I've noticed in the engine bay is that the large black
> hose (see photo here: http://www.coreaddicts.com/hose.jpg) connecting
> to the air filter housing is very loose (despite my best efforts to
> tighten and make fit... going to try some padding of some sort or get a
> new smaller clamp). Anyway, could that be it? Too much leaky air
> getting in there or something? I kinda ruled out ECU/AFM as cruising
> speeds are just fine. If I had dirty injectors wouldn't that effect all
> speeds etc? Thanks for any tips. I'm terrible with motors, but will
> learn quick with this new Westy. :-)
>
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